Urinary lactate to creatinine ratio in neonates with perinatal asphyxia and its correlation with severity of hypoxic ischemic encephalopathy

Abstract

Background: Neonates with perinatal asphyxia are prone to development of hypoxic ischemic-encephalopahty (HIE). There are no reliable methods for prediction of HIE in these neonates. Objectives: To determine urinary lactate to creatinine ratio in neonates with perinatal asphyxia and its correlation with severity of hypoxic ischemic encephalopathy. Material and Methods: A prospective study was carried out at neonatal intensive care unit (NICU) at Department of Pediatrics, MLB Medical College Jhansi. 50 neonates born at > 36 weeks gestation with perinatal asphyxia, admitted in neonatal intensive care unit were taken as cases and 50 normal newborns with gestational age > 36 week included as control. We measured the ratio of lactate to creatinine in urine sample by colometric technique within 24 hr after birth both in cases and controls. All newborns were followed for 7 days during their stay in hospital for development of HIE. The results were correlated with the subsequent presence or absence of HIE. Results: The study revealed that mean urinary lactate to creatinine ratio during first 24 hours of life was higher in asphyxiated neonates than control group(5.35±4.59 vs 0.18±.07), the difference was found to be statistically highly significant (z=7.693; p=<0.0001). The grade of HIE correlated with the greater urinary lactate to creatinine ratio among cases and was significant (p=<0.0001). Conclusion: The urinary lactate to creatinine (Urinary L/C) ratio in newborn infants with asphyxia is significantly increased early in course of the disease which can be used as useful parameter for predicting the development of hypoxic ischemic encephalopathy.

Early predictors of brain damage in full-term newborns with hypoxic ischemic encephalopathy

“… 28 Another study found a higher urinary L/C ratio in HIE infants and this study was done after 24 hours from delivery to avoid delayed urination that may occur after birth. 29 In our study, we excluded any HIE infants not passing urine in the first 6 hours from the start to avoid this problem. Also, Ghotbi and Najibi reported a higher urinary L/C ratio in HIE infants within the first 6 hours after birth, which was 11-fold greater than the control group, and this ratio decreased to become 5-fold 24 hours after birth.…”

“…This finding was confirmed in previous studies that found a correlation between different severities of HIE infants depending on clinical examination and blood gases with the elevated levels of serum CKBB and urinary L/C ratio early after birth. 9 , 29 , 30 , 36 There was a case report about an infant that had a very high CK-BB >26.000 IU/L and that developed some neurodevelopmental delay in spite of receiving brain hypothermic therapy. 40 Against our study, Huang et al found a nonsignificant trend for the urinary L/C ratio to increase with the severity of the HIE.…”